This specification relates to generating descriptive text for images.
The Internet provides access to a wide variety of documents, such as image files, audio files, video files, and web pages. A search system can identify documents in response to a text query that includes one or more search terms or phrases. The search system ranks the documents based on their relevancy to the search query and importance and provides search results that link to the identified documents. The search results are typically ordered for viewing according to the rank.
For searches directed to images, the search system can identify images that are relevant to a search query based, in part, on text associated with the image. For example, an image may have one or more labels that include text associated with the image. The labels may be from metadata for the image, or may be text presented near an image on a document, such as a web page.